骨髓间充质干细胞向肝细胞分化过程中肝细胞相关转录因子的表达  

Expression of Hepatocyte-enriched Transcriptional Factors during the Differentiation of Bone Marrow Mesenchymal Stem Cell-derived Hepatocytes

作　　者：金晔[1] 曲强[1] 周立[1] 纪文娟[1] 赵磊[1] 何小东[1] 

机构地区：[1]中国医学科学院北京协和医学院北京协和医院基本外科,北京100730

出　　处：《中国医学科学院学报》2009年第3期330-334,I0004,共6页Acta Academiae Medicinae Sinicae

基　　金：北京市重点学科项目基金(HK100230446)~~

摘　　要：目的观察体外诱导大鼠骨髓间充质干细胞向肝细胞分化过程中肝细胞相关转录因子的表达和分布。方法从大鼠骨髓中分离间充质干细胞,体外诱导分化为肝细胞。采用半定量逆转录-聚合酶链反应(RT-PCR)方法比较肝细胞分化过程中转录因子肝细胞核因子4α(HNF4α)、CCAAT增强子结合蛋白α和β(C/EBPα和C/EBPβ)在诱导分化组和对照组中的表达水平;免疫荧光染色方法检测HNF4α在细胞中的表达定位。结果在肝细胞分化成熟过程中,转录因子HNF4α和C/EBPα的mRNA表达水平在诱导分化早期的细胞中显著高于对照组细胞,而C/EBPβmRNA表达水平在分化成熟的细胞中显著高于对照组细胞(P<0.05)。免疫荧光染色结果显示,HNF4α定位于分化细胞核内。结论在肝细胞分化过程中,转录因子HNF4α、C/EBPα和C/EBPβ呈特征性时序表达,表明骨髓间充质干细胞在向肝细胞分化时,肝细胞相关转录因子的表达与细胞分化的启动和维持密切相关。Objective To study the expression and distribution of hepatocyte-enriched transcriptional factors during the differentiation of hepatocyte by rat bone marrow stem cells in vitro. Methods Mesenchymal stem cells were isolated from rat bone marrow and induced into mature hepatocyte in vitro. The mRNA expression levels of hepatoeyte nuclear factor 4α （HNF4α） , CCAAT enhancer binding protein （C/EBP） α and were compared between induced and non-induced cultures using semi-quantitative reverse transcription-polymerase chain reaction. The distribution pattern of HNF4α was detected by immunofluorescence staining and observed by fluorescence microscope. Results Transcriptional factors HNF4α, C/EBPα, and C/EBPβ were expressed in the induced cells during the culture process. The mRNA expression levels of HNF4α and C/EBPα were significantly higher in induced cultures than those in non-induced cultures in the early stage, whereas C/EBPβ expression was significantly up-regulated in induced cultures at the late stage （P 〈 0.05 ）. Immunofluorescence staining showed that HNF4α was located in the cell nucleus of differentiated cells. Conclusion The characteristical time-dependent expression of transcriptional factors HNF4α, C/EBPα, and C/EBPβ during the hepatocyte differentiation by bone marrow stem cells demonstrates that the expressions of these transcriptional factors are closely related to the initiation and maintenance of hepatocyte differentiation.

关 键 词：骨髓间充质干细胞 肝细胞 转录因子 

分 类 号：Q291[生物学—细胞生物学]